<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8" />
    <title>变量的作用域练习题</title>
</head>
<body>
    <script>
        var a = 'a9';
        function fl(){
        var a = 'b9';
        console.log();
        }
        fl();
        console.log(a);
    </script>
</body>
</html>